ABSTRACT
In July 2013, the European Regulation (EC) No 1223/2009 came into effect in order to secure cosmetic products. The content-containing interaction between the packaging and the product must be considered for the safety assessment. Indeed, some compounds are able to migrate from the packaging to the product and may be harmful to the consumer health. This is why a first test was established by EXPERTOX laboratory in 2012 to deal with this new regulation. A new analytical method was developed and validated for the quantification of 23 substances able to migrate from the packaging to the product. It was applied on a plastic packaging with the five simulants of migration. To evaluate the content-containing interaction, a gas chromatography-mass spectrometry method was developed and validated. Liquid-liquid extraction was used to extract contaminants (thirteen phthalates and ten substances of very high concern) from migration simulants. Calibration curves showed good linearity regression from 2 to 50 µg mL-1 for nineteen molecules and from 5 to 45 µg mL-1 for the others. The limits of quantification were respectively 2 and 5 µg mL-1 . The accuracy, precision, repeatability of the analytical method and extraction yields were acceptable. No molecule was found in simulants of migration, so the potential contaminants present in the packaging did not migrate. A gas chromatography-mass spectrometry method and liquid-liquid extraction were validated for 23 molecules and can be used for the evaluation of the content-containing interaction of cosmetic products. Both quantification and extraction procedures are more robust and faster than previous method.
ABSTRACT
OBJECTIVE: Compact Dry TC, a rapid method kit for determining aerobic colony counts, has been developed by Nissui Pharmaceutical Co. for food application. These plates are pre-sterilized and contain culture medium, a cold-soluble gelling agent and a colour redox indicator for rapid enumeration. In this study, the alternative method is compared with the standard method ISO 21149:2006 - Cosmetic - Microbiology - Enumeration and detection of aerobic mesophilic bacteria, for cosmetic emulsions application. METHODS: An oil-in-water (o/w) cosmetic emulsion was contaminated with a pool of bacterial strains (Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 6538 and Pseudomonas aeruginosa ATCC 9027). One millilitre of samples was spread on agar as described in ISO 21149. The colonies were enumerated after 3 days of incubation. At the same time, 1.2 mL samples were spread on Compact Dry TC kits. The kit was incubated at 35°C ± 1°C for 48 h, and the colonies were enumerated. Accuracy determination was carried out using six replicates at four levels of concentrations (10, 50, 100 and 250 CFU mL-1 ). The repeatability study was carried out using 12 replicates at four levels of concentrations (10, 50, 100 and 250 CFU mL-1 ). Variations relative to the analyst and to the batch of emulsion have been investigated. RESULTS: The linear correlation coefficients of Compact Dry TC Kit enumeration with standard method ISO 21149:2006 was 0.9999. In comparison study, no apparent differences were noted between the Compact Dry TC kit and the reference method ISO 21149, for the detection level of aerobic microorganisms. Relative accuracy, repeatability and intermediate precision studies were acceptable. In the repeatability study, the Shapiro-Wilk test has confirmed the normally distribution of the twelve assays. No significant variations in Compact Dry TC count results were observed with different analysts and different batches of emulsion. CONCLUSION: The results showed that the two compared methods 'Compact Dry TC' vs. 'conventional pour plate' performed equally well. Demonstration was achieved that the Compact Dry TC method may constitute a useful alternative tool for rapid enumeration of aerobic mesophilic bacteria in cosmetic emulsions.
Subject(s)
Colony Count, Microbial , Cosmetics , Emulsions , Oxidation-ReductionABSTRACT
OBJECTIVE: Challenge test (CT) is essential to assure the efficiency of the preservative system in products. A previous study realized by our staff in 2012, carried out to evaluate the influence of three parameters (ethanol, pH and water) on the microbiological cosmetics products conservation. Following this work, a correlation between aw (based on the glycerine concentration) and the selected parameter has been demonstrated. In the present study, smaller limits of ethanol, pH and glycerine were applied to determinate CT necessity. METHODS: Sixteen stables O/W cosmetics creams with different concentration of ethanol (1-19%), glycerine (3-16%) and different pH (6-11) were formulated. To evaluate the efficiency of the different formulations, CTs were performed according to the International Standard ISO 11930:2012. To determine the influence of the parameters, a D-optimal plan generated by Design Expert(®) was applied. Design of Experiments software offers to plan, estimate and control the statistics and models for factorial and no-factorial designs. RESULTS: Challenge tests results show that 10 formula passed criteria A, two passed criteria B and four are not conform. Mostly, an ethanol concentration higher than 16% exempts products of CT. It has been shown that an ethanol concentration between 10.5% and 16%, and an glycerine concentration >10%; or if the ethanol concentration is between 5% and 10.5%, glycerine is >6% and pH is ≥10, the CT is not required. Ethanol has a significant impact on conservation and especially when it is correlated with glycerine and pH. Finally, a glycerine concentration higher than 16% exempts products of CT. CONCLUSION: Following the analysis of the different concentration, a correlation between glycerine and ethanol that directly influence microbiological protection of cosmetics products has been established. Indeed, by controlling ethanol, pH and glycerine, many products may be exempted from the CT.
